New s_devlist command and various fixes.

New s_devlist command to list sound output devices (windows)
Now calling freelibrary to avoid memory leaks (windows)
Tweaked dmaHD default CVAR values.
Tweaked dmaHD mixer time sampling.
Changed code to be more C compliant and to remove compiler warnings.
Merge pull request #27 from p5yc0runn3r/816d42ff20275db33506cf288abfbe57fd961bb7

New s_devlist command and various fixes.